Authors:
Catarina Monteiro
1
;
2
;
Rosa P. Herrera
3
;
4
;
Susana Silva
1
and
Orlando Frazão
1
Affiliations:
1
INESC TEC—Institute for Systems and Computer Engineering, Technology and Science, Rua do Campo Alegre 687, 4150-179 Porto, Portugal
;
2
Department of Engineering Physics, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto, Portugal
;
3
Department of Electrical, Electronic and Communication Engineering, Public University of Navarra, 31006 Pamplona, Spain
;
4
Institute of Smart Cities (ISC), Public University of Navarra, 31006 Pamplona, Spain
Keyword(s):
Fiber Laser, Graphene Oxide, Saturable Absorption.
Abstract:
The use of graphene oxide (GO) as a saturable absorber for short pulses generation in an Erbium-doped fiber laser was studied and demonstrated. The saturable absorber consisted of a thin GO film, with a high concentration of monolayer GO flakes, spray-coated on the end face of a ferrule-connected fiber. By including the saturable absorber in the laser cavity and controlling the intra-cavity polarization, the generation of short-pulsed light was achieved under mode-locking and Q-switching operations. Under mode-locking operation, it was observed a pulse train with a fundamental repetition rate of 1.48 MHz, with a working wavelength centered at 1564.4 nm. In the Q-switch operation, a pulse train with a 12.7 kHz repetition rate and a 14.3 µs pulse duration was attained for a 230-mA pump current. Further investigation showed a linear dependence of the repetition rate with the pump power, attaining frequencies between 12.7 and 14.4 kHz.